DTC U0199, U1281, U128D (Power Seat Control Unit)

DTC U0199  : Power seat control unit lost communication with door multiplex control unit (DRLockSW frame)

DTC U1281  : Power seat control unit lost communication with MICU (MICU frame)

DTC U128D  : Lost communication with gauge control module (VSP/NE frame)

NOTE: 

• Refer to the DTC code shown on the display, and then inspect the connectors and terminals based on the instructions in the table below.
• The DTC may be stored due to the grounding failure or the power source failure at the transmitting control unit (the grounding inspection and the power source inspection on each control unit are required prior to this checking process).

DTC (Power Seat Control Unit)

NOTE:  If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .

1. Problem verification

   -1. Clear the DTCs with the HDS.

   Clear DTCs

   -2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

   -3. Wait for at least 6 seconds.

   -4. Check for DTCs with the HDS.

   DTC Description	DTC
   U0199 Power seat control unit lost communication with door multiplex control unit (DRLockSW frame)
   U1281 Power seat control unit lost communication with MICU (MICU frame)
   U128D Lost communication with gauge control module (VSP/NE frame)

   Are DTC U0199, U1281 or U128D indicated?

   YES 

   Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Check for loose or poor connections.

2. Open wire check (B-CAN_H, B-CAN_L lines)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Disconnect the receiving control unit connector.

   Power seat control unit connector A (20P)

   -3. Disconnect the transmitting control unit connectors.

   Power window master switch 37P connector

   Gauge control module 32P connector

   Under-dash fuse/relay box connector R (16P)

   -4. Check for continuity between the receiving control unit and the transmitting control unit on the B-CAN_H circuit and the B-CAN_L circuit as specified in the table while in the vehicle OFF (LOCK) mode.

   DTC	CIRCUIT NAME	RECEIVING CONTROL UNIT	TRANSMITTING CONTROL UNIT
   U0199	B-CAN_H	Power seat control unit connector A (20P) No. 16	Power window master switch 37P connector No. 28
   	B-CAN_L	Power seat control unit connector A (20P) No. 17	Power window master switch 37P connector No. 30
   U1281	B-CAN_H	Power seat control unit connector A (20P) No. 16	Under-dash fuse/relay box connector R (16P) No. 10
   	B-CAN_L	Power seat control unit connector A (20P) No. 17	Under-dash fuse/relay box connector R (16P) No. 11
   U128D	B-CAN_H	Power seat control unit connector A (20P) No. 16	Gauge control module 32P connector No. 26
   	B-CAN_L	Power seat control unit connector A (20P) No. 17	Gauge control module 32P connector No. 27

   Is there continuity?

   YES 

   The B-CAN_L to B-CAN_H wire is OK. Go to step 3.

   NO 

   Repair an open or high resistance in the wire(s).

3. Determine possible failure area (the receiving control unit or the transmitting control unit)

   -1. Reconnect all connectors.

   -2. Clear the DTCs with the HDS.

   Clear DTCs

   -3. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

   -4. Wait for at least 6 seconds.

   -5. Check for DTCs with the HDS.

   DTC Description	DTC
   U0199 Power seat control unit lost communication with door multiplex control unit (DRLockSW frame)
   U1281 Power seat control unit lost communication with MICU (MICU frame)
   U128D Lost communication with gauge control module (VSP/NE frame)

   Are DTC U0199, U1281 and U128D indicated?

   YES 

   Check for loose terminals and poor connections in the power seat control unit connector. Check is OK, replace the power seat control unit .

   NO 

   The power seat control unit is OK at this time. Replace the transmitting control unit.

   (Refer to the DTC code shown on the display, and then replace the control unit based on the instructions in the table below.)

   DTC	TRANSMITTING CONTROL UNIT
   U0199	Replace the power window master switch
   U1281	Replace the MICU
   U128D	Replace the gauge control module